Most free-standing cabinets of the type utilized in offices, such as lateral file cabinets or wardrobes, employ a housing which generally involves a substantially U-shaped upright side wall structure secured to top and bottom wall structures, with the front of the side wall structure defining a large opening for doors, drawers and the like. Such free-standing cabinets are normally of substantial size, and typically may have a width in the range of 30 to 48 inches, a depth in the range of 16 to 24 inches and a height of up to 6 feet. This size, coupled with the loads imposed on the cabinet, particularly when used for lateral files and the like, requires that the housing structure have substantial strength and rigidity. Such cabinets have typically employed an internal framework which is fabricated from channels, angles and the like, which framework is typically welded. Thereafter the housing is typically provided with an outer skin formed from thin metal plates which are secured, as by welding, to the underlying frame. The skin for the U-shaped upright side wall structure is typically formed from three separate pieces due to the size and fabrication technique of the housing structure, with one large skin being secured to and defining the rear or back wall, and two additional skins being secured to the frame and defining the side walls. This technique normally results in a weld or seam at the rear corners, often due to an overlap between the back and side skins, and in addition normally results in the corners being square. This results in the cabinet having an appearance from the back side which is unsightly, and hence such cabinets typically can be utilized only in situations where the back of the cabinet is directly adjacent a wall or other suitable structure.
Accordingly, the present invention relates to an improved cabinet which is believed to overcome many of the above-mentioned disadvantages. More specifically, this invention relates to an improved housing structure for a large-size free-standing cabinet, such as a lateral file cabinet. The housing structure employs an upright U-shaped side wall structure joined between top and bottom walls. However, the side wall structure employs a U-shaped metal skin which is formed in one piece so that the back and side walls are integrally joined together through rounded rear corners, with the front edges of the side walls also being rounded to form front integral edge strips which define the opposite sides of the front opening of the cabinet. With the improved arrangement of this invention, the cabinet can hence be utilized as a multi-purpose structure, including use in a free-standing open environment whereby the back of the cabinet is exposed but provides a desirable and pleasing appearance due to the back of the cabinet being provided with rounded corners which are free of weld lines or seams.
While small cabinets such as file drawer cabinets of the type attached below desk tops and work surfaces have at times utilized a U-shaped metal skin formed integrally of one piece, nevertheless such skin typically has been formed so as to define the sides and either the top or bottom wall of the cabinet. This configuration has been possible since such drawer units are of rather small size both widthwise and depthwise in contrast to lateral file cabinets, and are also not subjected to the severe loading which exists in lateral file cabinets.
In addition to the use of the integral U-shaped side wall skin on the cabinet of the present invention, as described above, the present invention also provides an interior frame formed from channels which are suitably welded to the skin so as to permit fabrication of the housing structure, whereby when the housing structure is completely fabricated, the channels effectively form two vertically rectangular frames disposed adjacent the front and rear of the cabinet so as to provide it with substantial strength and rigidity. In addition, the housing structure has a top wall which secures to the upper edge of the side wall structure, as by means of removable fasteners, whereby welding of the top to the side wall structure so as to provide additional strength, such as is typical with many of the known structures, is hence not required.
The present invention also provides an improved method for forming and fabricating the housing structure for the cabinet, which method includes the steps of initially providing a large substantially rectangular thin metal plate having the desired dimensions, bending the side edges of the plate to form the front wall edge portions, bending the upper edge of the plate to form a top flange, notching the top flange at four locations corresponding to the four corners of the housing, welding four vertically elongated channels to the inner surface of the sheet while the latter is still in a flat condition, which channels are disposed so that two channels are secured to the inner surface of each of the resulting side walls, and thereafter bending the sheet into its U-shaped configuration by forming rounded bends which create the rear corners of the housing. Bottom rails are then secured to and extend across the U-shaped skin adjacent the lower end thereof, with a bottom plate being welded over the bottom rails. Top rails are positioned to extend between and welded to the upper ends of the vertical channels, and a separately formed top wall or cap is then positioned so as to rest on the top flange and is secured thereto, as by screws or other suitable fasteners.
Other objects and purposes of the invention will be apparent to persons familiar with structures of this type, and methods of fabricating such structures, after reading the following specification and inspecting the accompanying drawings.